Is light the reason you’re getting heavier?

No, that title’s not just a really bad pun. It’s the result of a new study out of Japan that revealed being exposed to light at the wrong time can cause you to pack on the pounds.

What the researchers discovered was that among seniors, staying up late in a well-lit environment — combined with getting too little natural light in the morning — was associated with an increase in belly fat.

And that weight gain came about regardless of how much the subjects ate, exercised or what time they hit the sack.

Lots of light in the AM led to weight loss

By comparison, test subjects who were exposed to more intense light in the morning were more likely to lose weight.

The researchers tested over a thousand people for ambient light exposure by attaching light meters to their wrists. And of course, they also measured the subjects’ waist circumference, height and body weight.

Lead study author Dr. Kenji Obayashi of Nara Medical University School of Medicine called the findings the first evidence in humans that obesity can be related to a disturbance in our circadian rhythms, which are the body’s internal clock.

The results, he said, made sense, because of the very way human beings evolved, with “daytime high and nighttime low light intensity.”

Nix the tech before bed for a slimmer waist

Now, of course, even after we get into bed we spend time on our phones or iPads. And that kind of abnormal light exposure also zaps our secretion of melatonin, a hormone that influences how we use energy as well as how soundly we sleep at night.

So, put simply, if you want to try using the latest findings to drop some pounds, get more sunlight in the morning while cutting down on using all those devices at night.

Jenny Thompson is the Director of the Health Sciences Institute and editor of the HSI e-Alert. Through HSI, she and her team uncover important health information and expose ridiculous health misinformation, most notably through the HSI e-Alert.